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Biomedical subjects

Y Sano

Publications and source records attributed to Y Sano.

At least 127 records · Page 7Linked to original sources
PubMed1998

Visualization of cavitated vessels in winter and refilled vessels in spring in diffuse-porous trees by cryo-scanning electron microscopy

Xylem cavitation in winter and recovery from cavitation in the spring were visualized in two species of diffuse-porous trees, Betula platyphylla var. japonica Hara and Salix sachalinensis Fr. Schm., by cryo-scanning electron microscopy after freeze-fixation of living twigs. Water in the vessel lumina of the outer three annual rings of twigs of B. platyphylla var. japonica and of S. sachalinensis gradually disappeared during the period from January to March, an indication that cavitation occurs gradually in these species during the winter. In April, when no leaves had yet expanded, the lumina of most of the vessels of both species were filled with water. Many vessel lumina in twigs of both species were filled with water during the period from the subsequent growth season to the beginning of the next winter. These observations indicate that recovery in spring occurs before the onset of transpiration and that water transport through twigs occurs during the subsequent growing season. We found, moreover, that vessels repeat an annual cycle of winter cavitation and spring recovery from cavitation for several years until irreversible cavitation occurs.

Journal Article↗
PubMed1998

Inhibitory effects of pentamethine trinuclear cyanine dyes on ADP/Fe2+-induced lipid peroxidation in rat liver mitochondria: changes in the mode of action with the hydrophobic nature of the dyes.

The effects of various pentamethine trinuclear cyanine dyes, each of which has three alkyl chains, on ADP/Fe2+-induced lipid peroxidation in rat liver mitochondria were examined. Although the dye having the shortest -C2H5 chains (tri-S-C2(5)) did not show any appreciable effect, the dyes having -C4H9 (tri-S-C4(5)), -C7H15 (tri-S-C7(5)), and -C12H25 (tri-S-C12(5)) chains significantly inhibited lipid peroxidation, the most potent inhibitory effect being observed with tri-S-C7(5). The mode of antiperoxidation effect of the dyes was dependent on the length of the alkyl chains. The relatively hydrophilic dye tri-S-C4(5) was suggested to scavenge radicals more efficiently at or near the membrane surface rather than in the interior of the lipid membrane, whereas the more hydrophobic dye tri-S-C7(5) was suggested to scavenge radicals efficiently in the membrane rather than at or near the membrane surface. The hydrophilic/hydrophobic balance of the dye was found to regulate the site of action of the dyes.

Adenosine Diphosphate↗
PubMed1998

Effect of heparin on hemagglutination by equine arteritis virus.

Heparin inhibited hemagglutination (HA) by equine arteritis virus (EAV) as well as did HA by Aujeszky's disease virus (ADV), but failed to inhibit HA by parainfluenza virus type 3 (PIV-3). The minimal concentration of heparin required to inhibit 8 HA U of EAV was 0.1 U/ml. In addition, most EAV hemagglutinin was retained by heparin acrylic beads, as was ADV hemagglutinin, but was not PIV-3 hemagglutinin. Mouse erythrocytes failed to combine with the HA inhibitory factor of heparin. However, mouse erythrocytes treated with heparinase had greatly reduced agglutinability by EAV. All these findings suggest that a heparin-like molecule on the surface of mouse erythrocytes serves as the virus-cell receptor.

Animals↗
PubMed1998

Hemagglutination with crane herpesvirus.

A crane herpesvirus (CrHV) grown in chicken embryo fibroblast (CEF) cells was tested for hemagglutination (HA) with erythrocytes from a variety of species at 4 degrees C, room temperature and 37 degrees C. HA was observed at all temperatures with erythrocytes from mouse, ddY and BALB/c strains, but not with those from cattle, sheep and chicken. Mice, ddY strain, showed an individual variation in agglutinability of their erythrocytes and erythrocytes from BALB/c gave a higher HA titer. The HA activity was inhibited by the sera obtained from naturally infected cranes, experimentally infected duck and immunized rabbit with CrHV. HI antibody titers of these sera showed a closely positive correlation with their neutralizing antibody titers.

Animals↗
PubMed1998

Expression of mucin genes and carbohydrate epitopes in 19 human colon carcinoma cell lines.

The levels of mRNA corresponding to the MUC1, MUC2, MUC5AC, MUC5B, and MUC6 genes were determined in 19 human colon adenocarcinoma cell lines by the reverse transcriptase-polymerase chain reaction method using specific primers in an attempt to correlate to the levels of cell surface carbohydrate epitopes. All 19 cell lines expressed MUC1 and MUC5B mRNA, whereas MUC2, MUC5AC, or MUC6 mRNA were only detected in 8, 3, or 2 of 19 cell lines, respectively. Sialyl Lewis a carbohydrates, identified by the monoclonal antibody (mAb) CA19-9, and sialyl Lewis X carbohydrates. identified by mAb KM93, were observed, with most of the cell lines expressing multiple mucin core polypeptide genes but with few cell lines expressing only MUC1 and MUC5B. Sialyl Tn epitopes identified by mAb B195.3R11 and by mAb TKH-2 were strongly expressed on both of two MUC6-positive cells, whereas only a small portion of MUC6-negative cells expressed these epitopes. Strict correlation between mucin gene expression and any carbohydrate epitopes examined was not observed.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1998

Effect of rearing at non-permissive temperature on silkworm larvae infected with temperature-sensitive lef-8 mutant of bombyx mori nucleopolyhedrovirus.

A temperature-sensitive (ts) mutant of bombyx mori nucleopolyhedrovirus (BmNPV), ts-S1, contains a mutation in a putative RNA polymerase gene, which is involved in late viral gene expression. When 4th-instar silkworm larvae were infected with 1.0 x 10(5) TCID50 of ts-S1 per larva and reared at 33 degrees C, the titre of budded virus (BV) and number of occlusion bodies (OBs) in the haemolymph of the infected larvae were very low in the early stage but markedly increased in the late stage of infection. In contrast, a rapid increase in both BV titre and OB number was detected in the haemolymph of infected larvae reared at 25 degrees C. LD50 values of ts-S1 and wild type BmNPV (wtBmNPV) for 4th-instar larvae were 2.41 and 0.96 TCID50 per larva at 25 degrees C, and > 1.0 x 10(6) and 1.70 TCID50 per larva at 33 degrees C, respectively. These results indicate that the virulence of ts-S1 for the larvae reared at 33 degrees C was markedly reduced. To examine further the reduction of ts-S1 virulence at the non-permissive temperature of 33 degrees C, silkworm larvae were infected with ts-S1 at the multiplicity of 1.0 x 10(2) - 1.0 x 10(6) TCID50 per larva, reared for various time at 33 degrees C and then shifted to 25 degrees C. Longer rearing periods at 33 degrees C resulted in better survival rates indicating that the reduction of virulence of ts-S1 was proportional to cumulative rearing time at 33 degrees C. When large virus inocula were used, a growth alteration of larvae was preferentially induced. However, when small virus inocula were used, the appearance of abortive infection due to the non-permissive temperature became more evident.

Animals↗
PubMed1998

Construction of a cosmid library and physical mapping of Bombyx mori nucleopolyhedrovirus genome.

Bombyx mori nucleopolyhedrovirus (BmNPV) DNA was partially digested with BamHI and BglII, or EcoRI, and cloned into the cosmid pWE15. Eight cosmid clones possessing viral DNA fragments with a size range from 34.9 kb to 45.1 kb were obtained, and they covered the entire viral DNA sequence. Using the cosmid library and plasmid libraries obtained previously, physical maps of BmNPV DNA were constructed for EcoRI, SmaI, PstI, SacI and SacII.

Baculoviridae↗
PubMed1998

Cytokine expression during orthotopic corneal allograft rejection in mice.

PURPOSE: The acquisition of cell-mediated immunity against donor antigens has been shown to be associated with rejection of orthotopic corneal allografts, but the mechanisms that cause corneal allograft destruction in grafted tissue remain obscure. To determine which T-cell subsets infiltrate graft tissue and cause graft rejection, cytokine expression was examined in corneal tissue after orthotopic corneal allograft. METHODS: BALB/c mice received orthotopic corneal allografts from either syngeneic BALB/c or allogeneic C57BL/6 donors. At 1 or 4 weeks after grafting, the mice were euthanatized, and their corneas were removed. Corneal tissue was frozen, homogenized, and placed in phosphate-buffered saline (PBS). Each sample consisted of five corneas in 500 ml PBS. After centrifugation, the supernatant was collected, and the concentration of the following cytokines was measured by enzyme-linked immunosorbent assay: interleukin (IL)-1alpha, IL-2, IL-4, IL-10, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha. RESULTS: Significantly increased amounts of proinflammatory cytokines (IL-1alpha and TNF-alpha) were detected in supernatants from all grafted corneas (both syngeneic and allogeneic) at 1 week after grafting. At 4 weeks after grafting, supernatants from normal corneas, corneas with syngeneic grafts, and corneas with accepted corneal allografts contained undetectable amounts of IL-2 and IFN-gamma, whereas supernatants from corneas with rejected corneal allografts contained significant amounts of IL-2 and IFN-gamma. There were no significant differences in the amounts of IL-4 or IL-10 among all samples. Histologic examination confirmed the expression of IL-2 and IFN-gamma in rejected corneal allografts. CONCLUSIONS: Because IL-2 and IFN-gamma are secreted primarily by T-helper type 1 (Th 1) cells, whereas IL-4 and IL-10 are secreted by T-helper type 2 (Th 2) cells, these results indicate that Th 1-type cytokines, rather than Th 2-type cytokines, contribute to the rejection of orthotopic corneal allografts in graft tissue.

Animals↗
PubMed1998

[Food and food additives hypersensitivity in adult asthmatics. I. Skin scratch test with food allergens and food challenge in adult asthmatics].

OBJECTS: The aim of this study was to investigate in adult asthmatics, which kinds of food allergen can cause a positive reaction by skin scratch test and cause symptoms when administered as a food challenge. SUBJECTS AND METHOD: Three thousand one hundred and two adult asthmatic patients were submitted to skin scratch tests with housedust mite. Japanese cedar extracts and 33 types of food. Sixty one adult asthmatic patients with a history of immediate, adverse reactions after food ingestion underwent open food challenge. RESULT: Six hundred and twenty five of 3102 subjects (20.1%) had a positive test to one or more food allergens. The commonest food allergens were shrimp (27.7%), crab (27.7%), yeast (23.8%) and buckwheat (15.8%). The positive tests of shrimp, egg and cow's milk were highest in patients under 20 years and decreased with age, however the test rates of crab and soybean were not influenced by age. Positive food challenge responses occurred in 30/60 subjects (50%). The foods, which most of ten provoked a reaction, were buckwheat, shrimp, crab and bread. CONCLUSION: Skin scratch test results in adult asthmatics were different from those in atopic children where the commonest foods with positive tests were egg, cow's milk and soybean. Except for patients with a previous life-threatening reaction. Food allergy should be diagnosed by food challenge where a patient's history of adverse reaction to food, positive skin test and RAST strongly support specific food reactivity.

Adult↗
PubMed1998

[Food and food additives hypersensitivity in adult asthmatics. II. Oral allergy syndrome in adult asthmatic with or without Japanese cedar hay fever].

OBJECTS: The aim of this study was to investigate whether oral allergy syndrome (OAS) in Japan has a particular association with Japanese cedar (JC) hay fever and which kinds of food allergen cause OAS. SUBJECTS AND METHOD: The questionnaire was answered by 463 adult asthmatics. Each patient was submitted to skin scratch tests with fresh foods and commercial food extracts. RESULTS: Of the 463 patients 45 (9.7%) were diagnosed as OAS. The foods, which most often provoked a reaction, were in order of frequency, melon, kiwi, crab and shrimp. The prevalence of OAS was higher in patients with JC hay fever than without JC hay fever. However, a higher prevalence of OAS was also found in house dust mite antibody positive patients than negative patients. There was no difference in the prevalence of OAS between JC hay fever and house dust mite antibody positive patients. CONCLUSION: It is suggested that OAS has no particular association with JC hay fever. OAS in Japan is associated with different foods from other countries such as Scandinavia where apple is frequently associated with OAS.

Adult↗
PubMed1998

[Effect of slow-release theophylline on airway inflammation in bronchial asthma].

Theophylline has been used as a bronchodilator in acute and chronic asthma management but recent evidences suggest that it has anti-inflammatory effects. Therefore, we investigated the therapeutic effect of slow-release theophylline in mild to moderate asthmatic patients. Symptomatic 19 patients with mild asthma who were treated with inhaled beta 2-agonist alone, and 17 subjects with moderate asthma who were treated with moderate dose of inhaled corticosteroid (beclomethasone dipropionate, BDP, 400-800 micrograms/day) were enrolled to the present study. After two-week run-in period, slow-release theophylline was administered for six to eight weeks and asthma symptoms, respiratory function, airway inflammation evaluated by the inhalation of hypertonic saline, and airway reactivity to histamine were investigated during observation period and after treatment. Asthma symptom score was significantly improved after theophylline treatment in both groups. Morning peak expiratory flow was significantly elevated but FEV1 was not significantly improved by the additional treatment with slow-release theophylline in both groups. Significant decreases in the percentages of total and EG2 + eosinophils in induced sputum demonstrated that slow-release theophylline has anti-inflammatory effect in patients with asthma despite the treatment with inhaled corticosteroid. Because recent reports suggest that theophylline may act as an anti-inflammatory drug even in low dose concentration, we also investigated the effect of plasma theophylline concentration on the airway inflammation. Patients were divided into two groups by the plasma concentration of theophylline, more than 10 micrograms/mL which is necessary to dilate airway and below 10 micrograms/mL, referred to as low dose concentration of theophylline. The results suggest that the administration of slow-release theophylline significantly decreased the percentages of both total and EG2 + eosinophils in induced sputum in both concentration groups. However, airway reactivity to histamine did not significantly change by the treatment. Taken together, we conclude that low dose treatment of slow-release theophylline has an anti-inflammatory effect and treatment with slow-release theophylline alone or the additional use with inhaled corticosteroid is an effective therapy for the management of mild to moderate asthma.

Adult↗
PubMed1998

[Food and food additives hypersensitivity in adult asthmatics. III. Adverse reaction to sulfites in adult asthmatics].

OBJECTS: Many studies show that sulfites cause multiple atopic manifestations by oral challenge in USA and Europe, however, there are few reports of sulfites sensitivity in Japan. The aim of this study establishes the presence of sulfites hypersensitivities in asthmatic subjects in Japan. SUBJECTS AND METHOD: Twenty adult asthmatic patients, who were non-steroid-dependent and without a suggestive history of sulfite sensitivity, underwent challenge with oral solution of metabisulfite. RESULT: Of 12 patients reacted to metabisulfite. They demonstrated airway obstruction 5 (41.7%), urticaria 4 (36.7%), skin manifestation 2 (16.7%) and nasal congestion 1 (8.3%). All patients who demonstrated airway obstruction, were sensitive to aspirin. CONCLUSION: Oral sulfite challenge should be made in patients with urticaria, that are not able to find out causative antigen, even though no suggestive history of sulfite sensitivity.

Adult↗
PubMed1997

Sonodynamically-induced in vitro cell damage enhanced by adriamycin.

Sonodynamically-induced cell damage and active oxygen generation enhanced by adriamycin (ADM) were compared in the same in vitro insonation set-up. Significant enhancement of the rates of both ultrasonically-induced cell damage and nitroxide generation was demonstrated with 40-160 microM ADM. Both rates correlated very well resulting in a correlation coefficient of more than 0.99. The enhancement of both rates was suppressed by 10 mM histidine. These results are consistent with the hypothesis that ultrasonically-generated active oxygen plays a major role in the sonodynamically-induced cell damage enhanced by ADM.

Animals↗
PubMed1997

Preventing symblepharon formation with a gelatin sponge in the eye of a patient with an alkali burn.

PURPOSE: To report a patient with symblepharon caused by an alkali injury whom we treated by using a gelatin sponge. METHODS: Four days after the burn, a gelatin sponge was inserted into the upper conjunctival sac to separate the raw conjunctival surfaces. RESULTS: The gelatin sponge adhered to the tarsal side of the upper fornix and was kept there for 11 days until no epithelial defect was visible in the bulbar conjunctiva. No symblepharon formation was observed 6 months after the injury. CONCLUSION: Application of a gelatin sponge proved to be a simple and effective way of preventing symblepharon formation after an alkali burn.

Alkalies↗
PubMed1997

Structural analysis of A-protein of cucumber green mottle mosaic virus and tobacco mosaic virus by synchrotron small-angle X-ray scattering.

The size and shape of A-protein of tobacco mosaic virus coat protein (TMVP) and cucumber green mottle mosaic virus coat protein (CGMMVP) were evaluated by means of small-angle X-ray scattering (SAXS) using a synchrotron radiation source, complemented by electron microscopic observations. The results imply that TMV and CGMMV A-proteins are composed of three and two subunits, respectively, stacked in the shape of an isosceles triangular prism at lower ionic strength. Considering the difference of the A-protein structure at higher and lower ionic strength, the globular core structure was proposed as a subunit which might be modeled as a thin isosceles triangular prism composed of four globular cores joined by rather flexible segments. These cores correspond probably to four helical regions in a subunit, and rearrange their relative positions according to the external conditions. A slight rearrangement of core positions in a subunit may result in the formation of A-proteins of various shapes.

Capsid↗
PubMed1997

Induction of donor-specific ACAID can prolong orthotopic corneal allograft survival in "high-risk" eyes.

PURPOSE: To examine the effect of donor-specific anterior chamber-associated immune deviation (ACAID) induction on the survival of orthotopic corneal allografts in neovascularized graft beds. METHODS: To induce donor-specific ACAID in recipients, peritoneal exudate cells (PEC) from C57BL/6 mice were incubated overnight with transforming growth factor (TGF)-beta. Cultured PEC were injected intravenously (i.v.) into BALB/c mice, and, 1 week later, these animals received orthotopic corneal allografts from C57BL/6 donors into neovascularized graft beds. Control mice received i.v. injection of syngeneic (BALB/c) PEC, cultured overnight with TGF-beta, and then received orthotopic corneal allografts from C57BL/6 donors. RESULTS: All corneal allografts (15 out of 15) were rejected within 2 weeks after grafting in the neovascularized graft beds of control animals. However, only 6 out of 16 (37.5%) of corneal allografts were rejected in recipients in which donor-specific ACAID had been induced by injection of allogeneic PEC cultured with TGF-beta. CONCLUSION: Previous studies revealed that rejection of orthotopic corneal allografts in neovascularized graft beds in mice correlated with acquisition of donor-specific delayed hypersensitivity (DH). The results of this study suggest that induction of donor-specific ACAID, which selectively impairs DH responses to donor antigens, effectively prolongs corneal allograft survival in "high-risk" eyes.

Animals↗
PubMed1997

Administration of aminoglycosides to hemodialysis patients immediately before dialysis: a new dosing modality.

We describe a new modality for administering aminoglycosides to hemodialysis (HD) patients, namely, a modification of the once-daily regimen which consists of administering the aminoglycosides over 60 min by drip infusion just before each HD session, with a preplanned peak concentration being reached at the beginning of the session and then with a rapidly decreasing concentration being achieved by the start of HD. The area under the concentration-time curve (AUC), i.e., the accumulation of the drug in the body, is thus minimized by this modality. Arbekacin (ABK) was given at a dose of 2 mg/kg of body weight to 10 HD patients infected with methicillin-resistant Staphylococcus aureus (MRSA) for 2 weeks (six sessions in total), resulting in the complete disappearance of MRSA in 5 patients. A high rate of elimination of ABK was attained for each patient while the patient was on HD (range, 0.20 to 0.42 h-1; mean 0.28 +/- 0.08 h-1) by using high-performance dialyzers provided with membranes made of either polymethylmethacrylate, cellulose triacetate (CTA), or ethylene vinyl alcohol. The best results were obtained with the CTA membrane, as revealed by the overall mass transfer coefficient (Ko). The AUC in the simulation model for the variation in the serum ABK concentration in this modality was calculated to be 40% of that of the conventional post-HD dosing modality, suggesting that a much higher dose could be administered to HD patients who receive HD thrice weekly (4 h per session), giving, e.g., 4 mg/kg initially and before the HD sessions, when there is an interval of 68 h from HD session to HD session, and giving 2 mg/kg before the other sessions.

Aged↗